Ubuntu Manpage: weston-drm - the DRM backend for Weston

NAME

       weston-drm - the DRM backend for Weston

SYNOPSIS

       weston-launch

       weston --backend=drm-backend.so

DESCRIPTION

The DRM backend is the native Weston backend for systems that support the Linux kernel DRM, kernel mode
setting (KMS), and evdev input devices. It is the recommended backend for desktop PCs, and aims to
provide the full Wayland experience with the "every frame is perfect" concept. It also relies on the
Mesa GBM interface.

With the DRM backend, weston runs without any underlying windowing system. The backend uses the Linux KMS
API to detect connected monitors. Monitor hot-plugging is supported. Input devices are found
automatically by udev(7). Compositing happens mainly in GL ES 2, initialized through EGL. It is also
possible to take advantage of hardware cursors and overlays, when they exist and are functional. Full-
screen surfaces will be scanned out directly without compositing, when possible. Hardware accelerated
clients are supported via EGL.

The backend chooses the DRM graphics device first based on seat id. If seat identifiers are not set, it
looks for the graphics device that was used in boot. If that is not found, it finally chooses the first
DRM device returned by udev(7). Combining multiple graphics devices are not supported yet.

The DRM backend relies on weston-launch for managing input device access and DRM master status, so that
weston can be run without root privileges. On switching away from the virtual terminal (VT) hosting
Weston, all input devices are closed and the DRM master capability is dropped, so that other servers,
including Xorg(1), can run on other VTs. On switching back to Weston's VT, input devices and DRM master
are re-acquired through the parent process weston-launch.

CONFIGURATION

       The DRM backend uses the following entries from weston.ini.

   Section output
       name=connector
              The KMS connector name identifying the output, for instance LVDS1.

       mode=mode
              Specify the video mode for the output. The argument mode can be one of the words off to  turn  the
              output  off,  preferred  to  use the monitor's preferred video mode, or current to use the current
              video mode and avoid a mode switch.  It can also be a resolution as widthxheight,  or  a  detailed
              mode line as below.

       mode=dotclock hdisp hsyncstart hsyncend htotal vdisp vsyncstart vsyncend vtotal hflag vflag
              Use the given detailed mode line as the video mode for this output.  The definition is the same as
              in xorg.conf(5), and cvt(1) can generate detailed mode lines.

       transform=transform
              Transform  for  the output, which can be rotated in 90-degree steps and possibly flipped. Possible
              values are normal, 90, 180, 270, flipped, flipped-90, flipped-180, and flipped-270.

OPTIONS

       When the DRM backend is loaded, weston will understand the following additional command line options.

       --connector=connectorid
              Use the connector with id number connectorid as the only initial output.

       --current-mode
              By default, use the current video mode of  all  outputs,  instead  of  switching  to  the  monitor
              preferred mode.

       --seat=seatid
              Use graphics and input devices designated for seat seatid instead of the default seat seat0.

       --tty=x
              Launch Weston on tty x instead of using the current tty.

ENVIRONMENT